Traversing one of the population centers of south Texas, the Nueces' 

 waters are considerably exploited by industrial, agricultural, and municipal 

 interests. A single large impoundment above Corpus Christi supplies the 

 major portion of irrigation in the semiarid counties of the Nueces valley. Mun- 

 icipal and industrial uses, particularly in the vicinity of Corpus Christi, place 

 a further drain on flows in the lower reaches. Expanding populations and the 

 resulting agricultural and industrial needs will place additional dennands upon 

 river flows. These new demands will be met by the construction of approxi- 

 mately seven more reservoirs along various reaches of the river systenn and 

 by increasing the capacity of the existing reservoir. 



Various federal agencies, including the Bureau of Reclamation, the 

 Soil Conservation Service, and the Corps of Engineers, are considering means 

 of utilizing flows of other Texas streams in addition to that of the Nueces. The 

 United States Study Commission recently submitted a report proposing a water 

 supply and control program for the entire state of Texas. Large variations of 

 climate exist in the state, and consequently, fresh-water supply is most crit- 

 ical in the arid and semiarid southern and western regions. The proposed 

 method of alleviating this imbalance is to divert the "surplus" runoff from the 

 major streams and transport this water to the semiarid lands by means of a 

 system of canals and pumping stations. Surplus runoff is considered as all 

 nonexploited flows entering the estuarine systems. 



A further indication of an expanding economy along the Texas coast 

 is the increased number of navigation channels, mineral developments, and 

 general construction projects which alter in varying degrees the estuaries and 

 their suitability as marine habitats. Projects for realignment, maintenance, 

 and addition of navigation channels - chiefly those associated with the Intra- 

 coastal Waterway - are frequently submiitted for an evaluation of their effects 

 upon marine fishery resources. General construction projects, a term em- 

 bracing such itenis as small fills, mineral drilling facilities, wharf construc- 

 tion, pipeline crossings, and others, generally have minimum effects upon 

 marine fishes. 



Severe alteration of water circulation and interchange through 

 "canalization" and segmentation of the estuaries by channels and the result- 

 ing spoil banks, is the principal danger from navigation projects, aside from 

 the actual physical loss of habitat. This is a major problem in Louisiana 

 where canalization is changing marshland ecology through increased salt- 

 water intrusion. Navigation projects often can be modified so that spoil dis- 

 posal results in a minimum loss of habitat. 



Individual construction projects of a general nature are usually not 

 sufficiently extensive to be considered detrimental. In large numbers, however. 



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